Privacy –Preserving Public Auditing for Data Security in Cloud Computing

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Privacy Preserving Public Auditing for Data Security in Cloud Computing. B97201006 . Outline. Overview of this paper Motivation and Initialization Detailed Mechanism Some Comments Reference. Overview of this paper. Overview of this paper. - PowerPoint PPT Presentation


Privacy Preserving Public Auditing for Data Security in Cloud Computing

Privacy Preserving Public Auditing for Data Security in Cloud ComputingB97201006 OutlineOverview of this paper

Motivation and Initialization

Detailed Mechanism

Some Comments

Reference Overview of this paperOverview of this paperIn one sentence,Ensure your data authentication in cloud?

Properties of cloud storageUsers always have availabe and scalable space Need not worry about running out of spaceUsers need not have real physical storage media Need not spend money on equipmentsData is not near your hand Data not accessible when network failureHow to make sure the data authentication?Overview of this paperSome instances threatening your data in cloud

Cloud Storage Provider deletes your data that you seldom access

Cloud Storage Provider hides data loss incidnets

Internal communication error in clusters of computers in Cloud(Amazon 2008,June 20)

Overview of this paperThe solution is:A third party checks you data authentication(Self-checking is too tiring)

Requirements:Checks authentication while preserving privacy[Exclusive]First model able to support scalable and efficient auditing[Exclusive]Security justified by concrete experiments[Mice.]No local copy of data, no more burden to usersMice. -> n6Motivation and InitializationMotivation and InitilizationMotivation:Check the authentication of data

Nonmenclature Explanation(1):TPA:Third Party AuditorUser:CSP:Cloud Storage ProviderAmazon

8Motivation and InitilizationNonmenclature Explanation(2)Public key: () keys for locking a boxPrivate key: () keys for unlocking a boxMAC: () message authentication code.Each piece of data has a MAC code, derived from its content(MD5) MD5("The quick brown fox jumps over the lazy dog")9e107d9d372bb6826bd81d3542a419d6 MD5("The quick brown fox jumps over the lazy dog.")e4d909c290d0fb1ca068ffaddf22cbd09Motivation and InitilizationPhase Nonmenclature:UserKeyGen: generate the keySigGen: gengerate the verification of meta data(MAC)CSP:Cloud Storage ProviderGenProof: generate proof of data correctnessTPA:Third Party AuditorVerifyProof:Audit proof from CSP(Amazon)10Have a little break...Motivation and InitilizationExample One: Privacy Leaking:MACAmazonAmazon


12Motivation and InitilizationExample Two: Finitely many checking times:NNMACAmazon


13Motivation and InitilizationItemExample 1Example 2Number of keys1NKey is given toMac is stored by AmazonFile is transferred toAmazon and AmazonExample1:Amazon:


14Detailed Mechanism(?)Detailed Mechanism(?)Algebra:Michael ArtinAlgebra

Essential Parts: Group Theory

Link: Here16Detailed Mechanism(?)Cryptography:Oded GoldreichFoundations of CryptographyEssential Parts: ???Link: Here

17Detailed Mechanism(?)User Initilization:AmazonAmazon


18Detailed Mechanism(?) = =19Detailed Mechanism(?) (stored in amazon)AmazonHash Code


(private key)

20Detailed Mechanism(?)Low Burden on Amazon:Constant large sending block(mathematical analysis)Theoretically, if amazon misses 1% data, TPA only needs to audit for 460, 300 samples with probability more than 99%, 95%Support for Batch AuditingMathematical Analysis

21Detailed Mechanism(?)Mathematical AnalysisStorage Correctness:Amazon can not generate valid response toward TPA without faithfully storing the dataPrivacy Perserving Guarantee:TPA can not derive usersdata conent from the information collected during the auditing porcess

22Detailed Mechanism(?)Performance Analysis(Real Expriments)Compared with old method(+Privacy)

Batch Processing

23Some CommentsSome Comments(?)TPACSP




Algebra:Michael Artin, 2nd Edition

Foundations of Cryptography:Oded Goldreich

Some slides from

Privacy Preserving Public Auditing for Data Storage Security in Cloud Computing(including some reference)27Q & A?


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